The present invention relates to rotary tiller and more specifically relates to the retention of rotary tiller tine hubs on driven shafts of the tiller.
One common way of connecting a rotary tiller tine hub to a driven shaft is the use of a bolt, which is received through aligned holes in the hub and shaft and held in place by a nut. This method of assembly is not entirely satisfactory because wrenches are required and the limited space between adjacent tines makes it difficult to work the wrenches. Additionally, the threads of the bolts are often abraded, during ordinary tilling operation, to the extent that the removal of the bolts for replacing worn or damaged tines is made difficult. Further, the bolt heads and nuts tend to engage plant stems and the like such as to cause them to wrap about the hubs.
Instead of using bolts and nuts for holding tine hubs on driven shafts, as described above, it is common to use a headed pin having a transverse hole therethrough, adjacent the end which is remote from the head, in which is received a cotter key or linch-pin. Inasmuch as the use of nuts and bolts is avoided with this manner of assembly, the attendant problems of working wrenches between the tines and difficulty of replacing the tines due to damanged threads are avoided. However, the problem of wrapping remains.
Another known rotary tiller construction embodies a constant diameter pin for retaining the tine hubs on the driven shafts, the pin having a hole adjacent one end thereof in which is received the opposite ends of a spring wire clip which is formed into an arcuate loop or bail that extends approximately 180.degree. in parallel spaced relationship to the hub and is received over the opposite end of the pin. This assembly method overcomes all of the afore-mentioned problems. However, the space between the loop portion of the wire clip and the hub, which permits the loop to be deflected over the end of the pin so as to permit disassembly of the hub from the draft, sometimes becomes filled with dirt and/or debris, which must be removed before the desired deflection can be accomplished. Further, the loop design of the wire clip results in it being relatively expensive.